Preterm infants and in particular infants born prior to 33 weeks gestation typically have poor respiratory and survival outcomes as a consequence of poorly developed respiratory systems. Preterm infants also have an increased risk of developing respiratory distress syndrome and/or bronchopulmonary dysplasia (BPD). The introduction of therapies such as antenatal corticosteroids and exogenous surfactants have improved respiratory and survival outcomes, however respiratory distress syndrome and BPD remain major causes of morbidity and mortality in the preterm infant. Further, some preterm and low birth weight infants are more likely to suffer morbidity from atopic conditions including asthma in later life. There is therefore a need for methods which promote respiratory development and thus minimise the incidence and/or risk of respiratory distress syndrome and/or BPD in preterm infants.
An inadequate nutrient supply in the neonatal period is hypothesized to contribute to the observed poor developmental outcome in preterm infants. The n-3 long chain polyunsaturated fatty acid, docosahexaenoic acid (DHA) is of particular interest in this regard because DHA is known to significantly alter a number of basic properties of cell membranes including permeability, fluidity and interactions with regulatory proteins. One such property includes a modulating effect on the activity of ion channels which may facilitate electrical signalling and cellular communication. The uptake of DHA into the developing fetus is maximised during the final trimester of pregnancy and as a result preterm infants do not receive the DHA in utero that is received by their full term counterparts.
The present inventors have surprisingly discovered that the respiratory development of an infant can be promoted by administration of DHA.